Using Chi-Square Tests
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Objective
I can apply the chi-square test to analyze observed and expected data.
Part 1 of 4
Warm-up video
Bozeman Science · 11:53Vetted channel
We don't generate video — this one is by Bozeman Science on YouTube. The practice questions and exit ticket below were drafted by AI for this objective, and every question is editable in the teacher guide.
Part 2 of 4
Key concepts
3 concepts
- 1
The Chi-squared (χ²) test is used to determine if the variation in data is due to chance or a specific variable being tested.
- 2
The null hypothesis states there is no statistical difference between observed and expected values; this hypothesis is either accepted or rejected based on whether the calculated χ² value exceeds the critical value.
- 3
Degrees of freedom are calculated as the number of outcomes minus one, and the critical value is found on a chart, typically using a p-value of 0.05.
Part 3 of 4
Practice
7 questions
What is the purpose of the Chi-square test?
In the Chi-square formula, what do 'O' and 'E' represent?
Part 4 of 4
Exit ticket
Quick comprehension check
“In an experiment, you expect to see 50% purple flowers and 50% white flowers. You observe 60 purple and 40 white flowers. Calculate the χ² value. Show your work.”
Sample answer included in the free materials
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